Anthony A. Tappenden (plaintiff), a car dealer, entered into an installment contract with William Artus for the purchase of a van. Tappenden allowed Artus to take possession of the van prior to Artus’s payment of the full purchase price. The van suffered a breakdown, and Artus arranged for its repair by Rayleigh Garage Ltd. (Rayleigh) (defendant). Rayleigh’s mechanics did not know that Artus was not the van’s owner. Artus failed to pay Rayleigh for the repairs. Shortly after the van’s breakdown, Tappenden withdrew his permission for Artus’s possession of the van. Tappenden located the van and demanded that Rayleigh return it. Rayleigh claimed a mechanic’s lien and refused to return the van until its receipt of payment for the repairs. Tappenden sued Artus and Rayleigh in Southend County Court for the van’s return and for damages. Tappenden asserted that he had not authorized the van’s repair and that he should have made any necessary repairs, because he was a mechanic. Rayleigh counterclaimed for a declaration that it had a mechanic’s lien on the van. The judge dismissed Rayleigh’s counterclaim, entered judgment for Tappenden, and ordered Rayleigh to return the van. Rayleigh appealed.