Ep 3.

The episode titled "The New Siren" of Robocar Poli season 4 introduces the audience to a new character named Selly, who is a fire siren. The episode begins with the fire brigade in the titular town getting busy in a rescue mission. As they are busy dousing the fire, the audience sees that Selly helps her team by tracing the origin of the fire from miles away, working as a lookout for the firemen.

Impressed by Selly's abilities, Roy and Amber, the two regular members of the rescue team, immediately invite her to join the team. Poli, who is the leader of the team, asks Selly to undergo a few tests before a final decision is made. Selly agrees and takes the tests, which she easily clears, leaving everyone impressed.

However, soon after joining the team, Selly begins to feel left out and underappreciated. She feels as though she is not given enough work and is only used in situations that do not require much of her skills. This leads Selly to start seeking attention and eventually become a little reckless.

During one of the rescue missions, Selly ends up breaking Roy's crucial tool, which leads him to lose his cool at her. Selly feels disheartened and runs away from the team. As she is sulking in a corner, she gets to witness an accident at a construction site.

Without any hesitation, Selly jumps into action, making use of her siren to alert everyone to the accident. She then uses her unique abilities to check the stability of a bridge, which helps the team devise a plan to save people stuck on the bridge. Thanks to Selly's efforts and bravery, everyone is rescued, and the team is amazed at her skills.

After the mission, Poli praises Selly for her role in the rescue mission, and the team welcomes her back with open arms. The episode ends with Selly finally feeling appreciated and part of the team.

In conclusion, "The New Siren" episode of Robocar Poli season 4 is an excellent addition to the show's collection. The episode focuses on how new members need to be appreciated and given the right amount of space to integrate into a new team. The introduction of Selly, the fire siren, offers a unique perspective into what it means to be part of a rescue team. The episode's lesson on the importance of recognizing the roles each team member plays and appreciating their unique abilities is both touching and educative. Overall, it's a great episode filled with action, emotions, and valuable lessons.