Didier Mathure, a brilliant space engineer, has not recovered from the explosion of his CRISTAL rocket, which he is appointed against his will to head GEPAN, a group for the study of unidentified aerospace phenomena. A rain of pink flamingos is at the origin of the first mystery that he needs to solve.

Didier has to deal with his new team: Marcel believes that the postcards sent by André, the former director of GEPAN, are coded, Rémy is enthusiastic about a potential extraterrestrial landing and Véra answers calls from witnesses of unidentified phenomena while taking care of Hatshepsout, the flamingo she has taken in. Didier learns that a commission has been created to investigate the explosion of the CRISTAL rocket and that Elise, his ex-wife, will be part of it.

The GEPAN, in turmoil, is preparing for the big ufological meetings where the team must make a good figure. Didier resolves to accept a deal with Commander Delbrosse, of Military Security, to obtain information. Marcel confides in Didier: the postcards sent by the former director of GEPAN make it possible to identify witnesses of an unknown phenomenon, who have mysteriously disappeared.

Didier and Véra try to understand what happened to Hatshepsout, the flamingo, who vanished! But the more they look for a rational answer, the more they lose their footing. Marcel thinks that a military plot is brewing behind the disappearance of four witnesses to the same phenomenon. Didier understands that his delay at his son's school show is due to a time leap.

Véra, disappointed by Didier, resigns from GEPAN and seeks answers from Zorel, the creator of the Cosmic Order, who claims to have met extraterrestrials. Didier and Marcel try to get their hands on a tape of the mysterious phenomenon filmed in Gondrecourt. Rémy must prove himself as an investigator with an unexpected case: a pond whose water has been transformed into a gigantic pile of shoes.

Didier faces the commission of inquiry which assesses his responsibility in the explosion of the CRISTAL rocket. His ex-wife, Elise, is one of them. Zorel is ready to deliver to GEPAN the film sought by the army which would be the proof of a UFO phenomenon, provided that Didier helps him to escape.

The missing witnesses resurface while Didier wonders about this unknown phenomenon which generates electromagnetic disturbances and influences the course of time. Véra and Rémy try to unravel the mystery of the shoe pond. The noose is tightening around Didier: if he wants to join Elise and work on the ARIANE aerospace project, he has one month to close GEPAN.

Commander Delbrosse gives Didier an ultimatum to prove that the UFO threat is real. Elise and Didier start working together again but Elise becomes concerned when she sees that Didier is beginning to believe in the possibility of extraterrestrial life. Véra goes to meet one of the witnesses who was in contact with the phenomenon to understand what he experienced.

Following the crash of a satellite that everyone takes for the explosion of a flying saucer, Didier is the guest of the 8 P.M. newspaper. Rémy is afraid of being accused of the destruction of the satellite and of losing his position at GEPAN. Vera thinks the key to the mysterious phenomenon lies in the memories of the four witnesses. She helps them remember when they were in contact with the phenomenon.

The office is in turmoil: while they are trying to establish a link between the four witnesses of the phenomenon, a young American director arrives at GEPAN, where he wants to shoot his next film on UFOs. Didier does everything to dissuade him, at the risk of alienating the team. Didier and Elise try to temper their rebelling teen daughter Diane...

Didier and Véra decipher the message linking the witnesses to the phenomenon. While investigating a crop circle in a cornfield, Marcel discovers the existence of a prototype microwave weapon. He thinks they were fooled by Commander Delbrosse. Didier is disillusioned. Véra continues to believe that the supernatural facts they have been confronted with are share Didier as the common denominator.

The team is in shock: it has discovered Didier's report recommending the closure of GEPAN. Didier decides to resign. Elise and Didier find the cause of the explosion of the Cristal rocket. Didier understands that a large-scale attack is going to take place on the day of a demonstration in Larzac which his daughter is attending. Didier leaves to save her.